package com.atguigu.gulimall.product.web;

import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;
import com.atguigu.gulimall.product.vo.Catelog2Vo;
import org.redisson.api.*;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.ValueOperations;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.List;
import java.util.Map;
import java.util.UUID;
import java.util.concurrent.TimeUnit;

/**
 * @Author: fd
 * @Date 2021/7/6 16:00
 * @Description:
 */
@Controller
public class IndexController {

	@Autowired
	private CategoryService categoryService;

	@Autowired
	RedissonClient redisson;

	@Autowired
	private StringRedisTemplate stringRedisTemplate;

	@GetMapping(value = {"/","index.html"})
	public String indexPage(Model model) {
		//1、查出所有的一级分类
		List<CategoryEntity> categoryEntities = categoryService.getLevel1Categorys();
		model.addAttribute("categories",categoryEntities);

		return "index";
	}

	// index/json/catalog.json
	@GetMapping(value = "/index/catalog.json")
	@ResponseBody
	public Map<String, List<Catelog2Vo>> getCatalogJson() {
		Map<String, List<Catelog2Vo>> catalogJson = categoryService.getCatalogJson();
		return catalogJson;
	}

	@ResponseBody
	@GetMapping("/hello")
	public String hello(){
		// 1.获取一把锁，只要锁的名字一样，就是同一把锁
		RLock lock = redisson.getLock("myLock");
		// 2.加锁
		// 阻塞式等待。默认加的锁都是30s
		lock.lock();
		//1）、锁的自动续期，如果业务超长，运行期间自动锁上新的30s。不用担心业务时间长，锁自动过期被删掉
		//2）、加锁的业务只要运行完成，就不会给当前锁续期，即使不手动解锁，锁默认会在30s内自动过期，不会产生死锁问题
		//lock.lock(10, TimeUnit.SECONDS);   //10秒钟自动解锁,自动解锁时间一定要大于业务执行时间
		//问题：在锁时间到了以后，不会自动续期
		//1、如果我们传递了锁的超时时间，就发送给redis执行脚本，进行占锁，默认超时就是 我们制定的时间
		//2、如果我们指定锁的超时时间，就使用 lockWatchdogTimeout = 30 * 1000 【看门狗默认时间】
		//只要占锁成功，就会启动一个定时任务【重新给锁设置过期时间，新的过期时间就是看门狗的默认时间】,每隔10秒都会自动的再次续期，续成30秒
		// internalLockLeaseTime 【看门狗时间】 / 3， 10s
		try {
			System.out.println("加锁成功，执行业务..." + Thread.currentThread().getId());
			Thread.sleep(30000);
		} catch (InterruptedException e) {

		}finally {
			// 3.解锁
			// 设置解锁代码不执行，redisson会不会造成死锁？
			System.out.println("解锁成功..." + Thread.currentThread().getId());
			lock.unlock();
		}

		return "hello";
	}

	/**
	 * 保证一定能读到最新数据，修改期间，写锁是一个排它锁（互斥锁、独享锁），读锁是一个共享锁
	 * 写锁没释放读锁必须等待
	 * 读 + 读 ：相当于无锁，并发读，只会在Redis中记录好，所有当前的读锁。他们都会同时加锁成功
	 * 写 + 读 ：必须等待写锁释放
	 * 写 + 写 ：阻塞方式
	 * 读 + 写 ：有读锁。写也需要等待
	 * 只要有读或者写的锁都必须等待
	 * @return
	 */
	@GetMapping(value = "/write")
	@ResponseBody
	public String writeValue() {
		String s = "";
		RReadWriteLock readWriteLock = redisson.getReadWriteLock("rw-lock");
		RLock rLock = readWriteLock.writeLock();
		try {
			//1、改数据加写锁，读数据加读锁
			rLock.lock();
			s = UUID.randomUUID().toString();
			ValueOperations<String, String> ops = stringRedisTemplate.opsForValue();
			ops.set("writeValue",s);
			TimeUnit.SECONDS.sleep(10);
		} catch (InterruptedException e) {
			e.printStackTrace();
		} finally {
			rLock.unlock();
		}

		return s;
	}

	@GetMapping(value = "/read")
	@ResponseBody
	public String readValue() {
		String s = "";
		RReadWriteLock readWriteLock = redisson.getReadWriteLock("rw-lock");
		//加读锁
		RLock rLock = readWriteLock.readLock();
		try {
			rLock.lock();
			ValueOperations<String, String> ops = stringRedisTemplate.opsForValue();
			s = ops.get("writeValue");
			try {
				TimeUnit.SECONDS.sleep(10);
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			rLock.unlock();
		}

		return s;
	}


	/**
	 * 车库停车
	 * 3车位
	 * 信号量也可以做分布式限流
	 */
	@GetMapping(value = "/park")
	@ResponseBody
	public String park() throws InterruptedException {
		RSemaphore park = redisson.getSemaphore("park");
		//获取一个信号、获取一个值,占一个车位，阻塞式等待
		park.acquire();
		boolean flag = park.tryAcquire();
		if (flag) {
			//执行业务
		} else {
			return "error";
		}

		return "ok=>" + flag;
	}

	@GetMapping(value = "/go")
	@ResponseBody
	public String go() {
		RSemaphore park = redisson.getSemaphore("park");
		//释放一个车位
		park.release();
		return "ok";
	}


	/**
	 * 放假、锁门
	 * 1班没人了
	 * 5个班，全部走完，我们才可以锁大门
	 * 分布式闭锁
	 */

	@GetMapping(value = "/lockDoor")
	@ResponseBody
	public String lockDoor() throws InterruptedException {

		RCountDownLatch door = redisson.getCountDownLatch("door");
		door.trySetCount(5);
		door.await();       //等待闭锁完成

		return "放假了...";
	}

	@GetMapping(value = "/gogogo/{id}")
	@ResponseBody
	public String gogogo(@PathVariable("id") Long id) {
		RCountDownLatch door = redisson.getCountDownLatch("door");
		door.countDown();       //计数-1

		return id + "班的人都走了...";
	}

}
